Continuous intraoperative monitoring of pelvic autonomic nerves during TME to prevent urogenital and anorectal dysfunction in rectal cancer patients (NEUROS): a randomized controlled trial

Abstract

Background: Urinary, sexual and anorectal sequelae are frequent after rectal cancer surgery and were found to be related to intraoperative neurogenic impairment. Neuromonitoring methods have been developed to identify and preserve the complex pelvic autonomic nervous system in order to maintain patients' quality of life. So far no randomized study has been published dealing with the role of neuromonitoring in rectal cancer surgery.

Methods/design: NEUROS is a prospective two-arm randomized controlled multicenter clinical trial comparing the functional outcome in rectal cancer patients undergoing total mesorectal excision (TME) with and without pelvic intraoperative neuromonitoring (pIONM). A total of 188 patients will be included. Primary endpoint is the urinary function measured by the International Prostate Symptom Score. Secondary endpoints consist of sexual, anorectal functional outcome and safety, especially oncologic safety and quality of TME. Sexual function is assessed in females with the Female Sexual Function Index and in males with the International Index of Erectile Function. For evaluation of anorectal function the Wexner-Vaizey score is used. Functional evaluation is scheduled before radiochemotherapy (if applicable), preoperatively (baseline), before hospital discharge, 3 and 6 months after stoma closure and 12 months after surgery. For assessment of safety adverse events, the rates of positive resection margins and quality of mesorectum are documented.

Discussion: This study will provide high quality evidence on the efficacy of pIONM aiming for improvement of functional outcome in rectal cancer patients undergoing TME.

Trial registration: Clinicaltrials.gov: NCT01585727 . Registration date is 04/25/2012.

Keywords: Autonomic nerves; Fecal incontinence; Intraoperative monitoring; Quality of life; Rectal cancer; Sexual dysfunction; Urinary dysfunction.

Fig. 1

Summary of study interventions/flow diagram. † In patients who did not undergo stoma closure, study visits are planed 6 and 12 months after TME. Assessment of IIEF/FSFI and WVS will not be carried out. NT: Neoadjuvant therapy, TME: Total Mesorectal Excision, SC: Stoma closure, IPSS: International Prostate Symptom Score, Qol: Quality of life due to urinary symptoms, IIEF: International Index of Erectile Function, FSFI: Female Sexual Function Index, WVS: Wexner-Vaizey Score, pIONM: pelvic intraoperative neuromonitoring

Fig. 2

Frequency and scope of study visits